<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
    <div class="container">
        <div class="row">
            <h3>Live Streaming</h3>
            <img id="video" src="/video_feed1" width="100%" alt="">

            <button id="button">阶段1完成</button>
        </div>
    </div>

    <script>
        let video_img = document.getElementById("video");
        let btn = document.getElementById("button");
        btn.onclick = function () {
            video_img.setAttribute("src","/video_feed2");
            console.log("Hello world")
            btn.style.display = "none";
        }
    </script>
</body>
</html>